Documentation/devicetree/bindings/regulator/rohm,bd71837-regulator.yaml

   1 # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/regulator/rohm,bd71837-regulator.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: ROHM BD71837 Power Management Integrated Circuit regulators
   8
   9 maintainers:
  10   - Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
  11
  12 description: |
  13   List of regulators provided by this controller. BD71837 regulators node
  14   should be sub node of the BD71837 MFD node. See BD71837 MFD bindings at
  15   Documentation/devicetree/bindings/mfd/rohm,bd71837-pmic.yaml
  16   Regulator nodes should be named to BUCK_<number> and LDO_<number>. The
  17   definition for each of these nodes is defined using the standard
  18   binding for regulators at
  19   Documentation/devicetree/bindings/regulator/regulator.txt.
  20   Note that if BD71837 starts at RUN state you probably want to use
  21   regulator-boot-on at least for BUCK6 and BUCK7 so that those are not
  22   disabled by driver at startup. LDO5 and LDO6 are supplied by those and
  23   if they are disabled at startup the voltage monitoring for LDO5/LDO6 will
  24   cause PMIC to reset.
  25
  26 #The valid names for BD71837 regulator nodes are:
  27 #BUCK1, BUCK2, BUCK3, BUCK4, BUCK5, BUCK6, BUCK7, BUCK8
  28 #LDO1, LDO2, LDO3, LDO4, LDO5, LDO6, LDO7
  29
  30 patternProperties:
  31   "^LDO[1-7]$":
  32     type: object
  33     $ref: regulator.yaml#
  34     description:
  35       Properties for single LDO regulator.
  36
  37     properties:
  38       regulator-name:
  39         pattern: "^ldo[1-7]$"
  40         description:
  41           should be "ldo1", ..., "ldo7"
  42
  43     unevaluatedProperties: false
  44
  45   "^BUCK[1-8]$":
  46     type: object
  47     $ref: regulator.yaml#
  48     description:
  49       Properties for single BUCK regulator.
  50
  51     properties:
  52       regulator-name:
  53         pattern: "^buck[1-8]$"
  54         description:
  55           should be "buck1", ..., "buck8"
  56
  57       rohm,dvs-run-voltage:
  58         $ref: "/schemas/types.yaml#/definitions/uint32"
  59         minimum: 0
  60         maximum: 1300000
  61         description:
  62           PMIC default "RUN" state voltage in uV. See below table for
  63           bucks which support this. 0 means disabled.
  64
  65       rohm,dvs-idle-voltage:
  66         $ref: "/schemas/types.yaml#/definitions/uint32"
  67         minimum: 0
  68         maximum: 1300000
  69         description:
  70           PMIC default "IDLE" state voltage in uV. See below table for
  71           bucks which support this. 0 means disabled.
  72
  73       rohm,dvs-suspend-voltage:
  74         $ref: "/schemas/types.yaml#/definitions/uint32"
  75         minimum: 0
  76         maximum: 1300000
  77         description:
  78           PMIC default "SUSPEND" state voltage in uV. See below table for
  79           bucks which support this. 0 means disabled.
  80
  81         # Supported default DVS states:
  82         #
  83         # BD71837:
  84         # buck | dvs-run-voltage | dvs-idle-voltage | dvs-suspend-voltage
  85         # ----------------------------------------------------------------
  86         # 1    | supported       | supported        | supported
  87         # ----------------------------------------------------------------
  88         # 2    | supported       | supported        | not supported
  89         # ----------------------------------------------------------------
  90         # 3    | supported       | not supported    | not supported
  91         # ----------------------------------------------------------------
  92         # 4    | supported       | not supported    | not supported
  93         # ----------------------------------------------------------------
  94         # rest | not supported   | not supported    | not supported
  95
  96       # BD71837 power outputs can either be controlled by the PMIC internal
  97       # hardware state machine or by software. If you need regulators to be
  98       # turned ON/OFF for example based on PMIC_STBY_REQ line (which toggles
  99       # PMIC HW state machine) - then you should set this property.
 100       # Tradeoff is that then SW can't control the ON/OFF state for this
 101       # regulator (other than invoking a PMIC state change).
 102       rohm,no-regulator-enable-control:
 103         description: |
 104           Enable/Disable control of this regulator must be left to the
 105           PMIC hardware state machine.
 106         type: boolean
 107
 108       # Setups where regulator (especially the buck8) output voltage is scaled
 109       # by adding external connection where some other regulator output is
 110       # connected to feedback-pin (over suitable resistors) is getting popular
 111       # amongst users of BD71837. (This allows for example scaling down the
 112       # buck8 voltages to suit lover GPU voltages for projects where buck8 is
 113       # (ab)used to supply power for GPU.
 114       #
 115       # So we allow describing this external connection from DT and scale the
 116       # voltages accordingly. This is what the connection should look like:
 117       #
 118       # |---------------|
 119       # |       buck 8  |-------+----->Vout
 120       # |               |       |
 121       # |---------------|       |
 122       #        |                |
 123       #        |                |
 124       #        +-------+--R2----+
 125       #                |
 126       #                R1
 127       #                |
 128       #        V FB-pull-up
 129       #
 130       # Here the buck output is sifted according to formula:
 131       #
 132       # Vout_o = Vo - (Vpu - Vo)*R2/R1
 133       # Linear_step = step_orig*(R1+R2)/R1
 134       #
 135       # where:
 136       # Vout_o is adjusted voltage output at vsel reg value 0
 137       # Vo is original voltage output at vsel reg value 0
 138       # Vpu is the pull-up voltage V FB-pull-up in the picture
 139       # R1 and R2 are resistor values.
 140
 141       rohm,fb-pull-up-microvolt:
 142         description:
 143           Feedback-pin has pull-up connection to adjust voltage range. This is
 144           the used pull-up voltage before R1.
 145
 146       rohm,feedback-pull-up-r1-ohms:
 147         description:
 148           Feedback-pin has pull-up connection to adjust voltage range. This is
 149           the used R1 resistor.
 150
 151       rohm,feedback-pull-up-r2-ohms:
 152         description:
 153           Feedback-pin has pull-up connection to adjust voltage range. This is
 154           the used R2 resistor.
 155
 156     required:
 157       - regulator-name
 158
 159     unevaluatedProperties: false
 160
 161 additionalProperties: false